Improvement in blasting-fuses



G. BLOEM. Blasting-Fuse.

Shy..

yUivrmm STATES Y PATENT OFFICE.

GUs'rAv BLOEM, or DssnLDonr, PRUssIA, GERMANY.

IMPROVEMENT IN BLASTlNG-FUSES.

Specification forming part of Letters Patent No. 216,1 '37,. dated June 3, 1879; application filed April 3o, 1819.

To all whom it may concern: .I

Be it known that I, GUsrAv BLOEM, of Dsseldortliny the Kingdom of Prussia and Empire of Germany, have invented a new and useful Improvement in Detonating-Primers, which improvement is fully set forth in the following specification, reference being had to the accompanying drawings, inwhich- Figuie 1 represents a longitudinal central sectionof a primerembodying my invention. 'Fig'. 2 is a detail view thereof Without the fuse. Fig. 3 is alongitudinal section of the same, showing a modication in the union of the shells. Fig. 4 is a side view of the inner shell detached. Fig. 5 is an end view thereof.

Fig. .6 is alike view of theouter shell.

Similar letters indicate .correspon ding parts. My invention relates to detonating-primers for exploding dynamite and other similar substances, as in blasting operations; and it con-r formed in the outer cap after the parts have been put into place, and to facilitate the formation of'this contraction the outer cap is Vmade of reduced thickness at or near its outer or open end, where the ,contraction is situated, while for the purpose of weakenin g the outer cap on its closed end ythe lsame is provided with a groove or depression at that point.

In the drawings, the letter A designates the outer cap or shell, and B the inner cap, of my primer, and C is the fuse. Both of these caps A B are preferably made of copper and have a cylindrical shape, the inner cap being of such diametertas to t within the outer cap, and of such length as to leave a space within or beneath it in the outer cap for the reception of a fulminating compound. In the inner or hole, d. 4

I place a suitable quantity of some fulminating compound in the outer cap,\A, as at e, and place the inner cap, B, into the same, so as to rest on the fulminate, as indicated. I then insert in the inner cap, B, the end of the fuse C, which is made of a thickness to t the cap, and finally contract or. crimp the side of the outer cap, as at f, Figs. l or 3. 'The contraction thus formed engages both theinner cap, B, and the fuse C, and Vhence ythe same are thereon rmly held in position. Said contraction f may be formed at a point within the outer or open end of the inner cap, B, as represented vin Fig. 1, so that` a corresponding portion of the inner cap becomes contracted, as at g, and this contraction of the inner cap is pressed into the fuse C; or the contraction f may be formed in that part of the outer cap which is beyond said end of the inner cap, as represented in Fig. 3, in which case said contraction of the outer cap forms a stop to the inner cap, and at the same time engages the fuse in a similar manner to the contraction g.

.It will be seen that the inner cap, B, forms a very effective means of closing the outer cap, while its hole d opens a communication between the fuse G and the fulminate.

The contraction fis situated near the open end of the outer cap, A, where the thickness of the cap is reduced, so that the contraction may be readily formed therein. This arrangement allows of making the body part of the outer cap, A, of such thickness as to give the same the required strength without making it impracticable to crimp or contract the cap at f. In order to adapt the inner cap, B, to said reduction in the thickness of the outer cap, A, the inner cap is tapered, as shown in Fig. 2.

It is desirable to weaken the outer cap, A, on its closed end or head, and to effect this object I form in said end ofthe cap a groove, h, which in this example is ring-shaped, but which may be shaped like a cross or have any other rconceivable shape.

What I claim as new, and desire to secure by Letters Patent, is-

1. A detonating-primer in which are combined an outer cap or shell charged with a fulminating compound, an inner cap having a hole in its inner or closed end, and a fuse tted into the inner cap, all constructed and adapted -for use substantially as described.

2. The combination of an inner cap, having a hole in its inner or closed end and a' fuse iitted into said inner cap, with an outer cap charged with a fulminating compound, and having the contraction f, for the purpose of confining both the inner cap and the fuse, substantially as shown and described.

8. The combination, with an outer cap charged with a fulminating compound, and made of reduced thickness near its outer or open end, of an inner cap having a hole in its inner orclosed end, and afuse fit-ted into said inner cap, both held in their places by means of contractions formed in the reduced portion of the outer cap, substantially as shown.

4. The combination of an outer cap'chargedwith a fulminating compound, and weakened on its closed end by means of the groove h, an inner cap, B, having a hole in its inner or closed end, and a fuse tted into said inner cap, all constructed and adapted for use sub stantially as described.

In testimony that I claim the foregoing I have hereunto set my hand this 8th day of J auuary, 1879.

eUstrAv BLOEM.

Witnesses E. DITTLINGER, E. BUBE. 

